Compound cylinder



Patented Jan. 7, 19.36

PATENT oFFlcE L comoUNn cmNDEn nel-om c. Bowen, Denon, man., minor' t Hydraulic Brake Company. Detroit, Mich., a corporation of California Application February 1o, 1933, serial 10.656.175

This invention relates to pressure devices.

In the illustrated embodiment of the invention. a reservoir has formed in the bottom thereof a double diametral cylinder with that portion of the cylinder having the larger diameter extending from thev reservoir and provided with a removable head. The. head has a port controlled by a check valve and connected by a conduit to aV plurality of uid pressure actuated motors which are connected in'turn by a conduit to a relief valve in the wall of the reservoir.

A piston in the cylinder has a plurality of heads of diierent diameters positioned for reciprocation in the corresponding portions of the cylinder. Arranged between the piston heads are valves and control means for the valves including a spring-pressed pistony operable upon predetermined pressure to render the pistons ineffective.

The control means is iirst operable upon a predetermined pressure to release a valve in the head of the piston having the larger diameter to render this piston ineiective, and, secondly, upon a higher predetermined pressure to release a valve controlling a passage through the piston having the smaller'diameter and to return the iiuid to the reservoir.

The operating mechanism includes an actuator mounted in the reservoir between the relief valve and the piston. 'Ihis actuator, when in the position of rest, retains the relief valve in open position andfunctions as a stop for the piston, and when actuated to move the piston on its compression stroke dlsengages the relief valve so that it may close to inhibit the return of fluid to the reservoir.

An object of the invention is to provide a iluid pressure device which may be used for various purposes, and particularly where it ls desired to build up high pressures. p

Another object of the invention -is to provide a uid pressure device having iiuid pressure actuat- 'ed motors connected thereto and an actuator therefor arranged for successively actuating the device and-a relief valve for the motors.

with this object in view, the invention consists in the parts and combination to be hereinafter set forth and claimed, with the understanding that the several necessary elements comprising the invention may be varied in constructon, .proportion and arrangement. without departing from the spirit and scope of the appended claims.'

In order to make the invention more clearly understood, I have shown in the accompanying drawing means lfor carrying the same into practical eect without limiting the invention in its usefuhapplications to the particular constructions which, for the purpose of explanation, have been made a subject of illustration. ti In the drawing forming a part of this speciflca- I onz- -1 Figure 1 is a sectional view of a compound cylinder embodying the invention.

Figure 2 is a sectional view substantially on line 2--2, Figure 1, and l0 Figure 3 is a top plan view.

Referring to the drawing for more specific details of the invention, I0 represents a support having bolted or otherwise secured thereto .a housing I2 including a reservoir I 4 having a iilling pen- 15 ing I6 fitted with a plug I B. The housing has an extended top portion 20 provided with an opening and a cover 22 for the opening.

Formed integral withthe housing and communicatin'g with the reservoir I4 is a sleeve 24 zo having tted therein a valve cage 26 encasing a spring-pressed ball valve 28 controlling .the passage or communication between the sleeve and the reservoir. The passage has therein a pin 30 litted with sufilcient clearance to permit the free 26 passage of fluid or liquid. The pin extends into the reservoir and is 4adapted to open the valve, movement of the pin in opening the valve being limited by a stop 32 for arresting the actuator, to be hereinafter described. The sleeve also has 30 threaded therein a coupling 34 for connecting a return pipe 36.

` The housing I2 has formed therewith in the bottom of the reservoir a cylinder 38 having. a

portion extending from the wall of the housing. 35

The cylinder has a double diametral bore. The

inner end of this cylinder is slotted as indicated at 4B, and threaded inthe outer end of thevcylinder is a .plug 42. This plug is axially bored for the reception of a spring-pressed valve 44 and a 4 coupling 4i for the attachment of a pipe line 48. Positioned for reciprocation ln the cylinderis a compound piston comprising a small piston 50 of the piston has threaded axially therein a double diametrai sleeve 6I and positioned on the head of the piston is a leak-prooi cu'pn held in 55 diameter.

i 88 is opened by the pressure to permit the position by a spring 64 interposed between the cup and that portion of the sleeve having the larger diameter.

The sleeve 60 has a plurality of ports 63 and a piston head 65 positioned for reciprocation in that portion of the cylinder having the larger This head is tted in the cylinder with suitable clearance, or it may have channels 66 providing passageways for the fluid or liquid, and the head has a central port 68 controlled by a ball valve 10. The head has positioned thereon a leak-proof cup 'I2 and a disc 14 held against displacement by a spring 16 interposed between the disc i4 and the plug 42 in the outer end of the cylinder.

Positioned for reciprocation in the sleeve 60 is a piston 'I8 having a skirt 80 and a concentric portion 82 of smaller diameter than the piston and extending beyond the headv of the piston. This extended portion controls the ball valve 10. As shown, the extended portion 82 has an axial bore or passage 84 and a plurality of ports 86 controlled by a ball valve 88 urged to close the passage 84 by a spring 90 which also urges the piston 18 to actuate the ball valve 'l0 to close the port 68. The head of the piston'l has thereon a leakproof cup 92 sleeved on the extended portion 82. a

The extended top portion 20 of the housing has formed thereon oppositely disposed bosses 84 and 96 bored for the reception of an operating shaft 88. The shaft has a double diameter and that portion of the shaft having the siauer diameter is threaded for the reception of a lever or actuator arranged to actuate the piston 50 and to control the valve 28. When in normal position the actuator retains the valve 28 in open position so that excess iiuid may be returned to the reservoir. The shaft has a circumferem' tial groove |02 in which is positioned a leakproof washer |04 seated on'an annular shoulder |06 in the boss 88. The shaft also has a knurled portion |08 to which may be secured an operating lever IIO.

Assuming that the device is properly connected' in a system and that the reservoir I4 andthe cylinder 38 are filled with suitable liquid or fluid,

by applying force to the operating shaft to move this shaft through an angle, .the actuator H0 is moved from the stop 32 causing the valve 28 to close. This movement of the actuator lapplies force to the piston. During the initial movement of the piston, fluid is subjected to pressure by the piston head 6,5 movable in that portion of the cylinder having the larger diameter, and upon attaining a predetermined pressure onv the fluid by this movement of the piston the ball 10 is urged by the pressure from its seat to open the port 68. This relieves pressure on the cup 'I2 and equalizes the pressure on both sides of the piston head 65.

The pressure is then received by the cup 62 on' the piston 50, also by the cup 92 on the piston 18 and by the ball valve 88. 'I'his transfer of the 'pressure is effected without losses. Upon further movement of the piston and attaining a second predetermined presure, the ball valve uid to iiow through the ports 86, the passages 84 and 56, the axial boreV 54, the groove 52, and past the body of the piston 50 to the reservoir.

AsY the piston moves to its retracted position the valve 44 closes and retains the fluid under pressure in the system. This pressure is releasedy when the actuator is moved to trip the valve 28 so that excess uid in the system may be returned to the reservoir. As the piston moves to its retracted position the cups 62 and 'i6 collapse, and fluid is drawn from the reservoir past the cups into the cylinder, thus lling the cylinder for a subsequent discharge stroke.

As illustrated in Fig. 1, the pipe line or conduit 48 controlled by the valve 44 has connected thereto a plurality of conventional fluid pressure actuated motors H2 which may be operatively connected to any suitable type of mecha-` nism it may be desired to actuate. In this particular illustration the bleed conduit 36 controlled by the valve 28 leads back from the mo- 2o tors H2 to the reservoir I4. During operation the valve 28 is normally closed so that fluid is forced through the pipe line 48 into the mo'- tors and when the actuator is moved to its retracted position the valve 44 is closed and the 26 valve 28 is tripped so that .fluid in the system may return to the reservoir.

Although this invention has been described in connection with certain specific embodiments, the principles involved are susceptible of numer- 80 ous other applications that may readily occur to persons skilled in the art. The invention is, therefore, to be limited only as indicated by the scope of the appended claims.

Having thus described the various features oi the invention, what I claim is new and desire to secure by Letters Patent is:-

1. A pressure device comprising a reservoir normally containing a liquid, a cylinder in the bottom of the reservoir below the liquid level and having anopen end communicating with the reservoir, said cylinder being adapted to discharge into and operate an expansible chamber motor, a return valve controlling an intake in the wall of the reservoir opposite the open end 45 of the cylinder, said valve being adapted to con- .trol the return of fluid from said expanslble chamber motor to said reservoir, a stop on the wall of the cylinder adjacent the valve, and a lever for actuating the piston and valve having its free end extending between the piston and the valve and adaptable when the piston is in retracted position to seat on the stop and retain the valve in open position.

2. An hydraulic system comprising a compressor and reservoir unit normally containing liquid to a level above the compressor, a circulatory uid line having an expansible chamber motor connected therein having one end connected with the compressor to receive fluid therefrom and its other end connected tothe reservoir to return uid thereto, a return valve con` nected in the iiuid line and arranged in the wall of said reservoir and a lever movable in the reso ervoir .between the compressor and valve and operable to actuate the compressor on' the compression stroke and to release the compressor and'open the valve on the retraction stroke.

HERBERT C. BOWEN. 

